不同成熟度桑葚的品质分析

Analysis of mulberry quality at different maturities

【目的】为桑葚的合理化应用和适时采收提供参考。【方法】以2个新疆良种‘黑妞’和‘贵妃’成熟度1~6的果实为材料,测定了果实营养相关指标和功能性相关指标,分析比较不同成熟度桑葚中各指标的差异,探讨成熟度与果实品质间的相关性。【结果】‘黑妞’和‘贵妃’果实在成熟度为4时内源物质含量具有显著差异,同时‘黑妞’果实内源物质含量总体要高于‘贵妃’;总酚、总黄酮和花青素含量整体上与果实成熟度具有正相关性,并且,这3类物质的含量在成熟度为6时均最高,分别为54.8、40.1和557.9 mg/g;‘黑妞’和‘贵妃’果实的蛋白质含量与果实成熟度均负相关,‘黑妞’果实在成熟度为5时含量最低(0.2 g/kg),‘贵妃’果实在成熟度为6时含量最低(0.1 g/kg);‘黑妞’果实的抗坏血酸含量与果实成熟度负相关,含量变化幅度小,在成熟度为6时含量最低(0.7 g/kg),而‘贵妃’果实在成熟度前3阶段未检测出抗坏血酸,从成熟度为4时开始出现抗坏血酸,说明这个阶段是抗坏血酸积累阶段;酚酸类含量和总酸含量与果实成熟度均负相关,在成熟度为6时达最低值,其中‘黑妞’和‘贵妃’果实中酚酸类含量最低值分别为30.3和2.2 mg/kg,总酸含量最低值分别为10.6和7.5 g/kg;在各种氨基酸中,‘黑妞’和‘贵妃’6个成熟度果实中天门冬氨酸的平均含量最高,分别为0.055和0.047 mg/g,其中成熟度为1时天门冬氨酸含量最高,分别为0.078和0.104 mg/g,该指标可被作为果实不同成熟期的风味评价指标。【结论】随成熟度的增加,各果实品质性状指标呈现明显的变化规律。‘黑妞’果实的营养物质总含量显著高于‘贵妃’,且‘黑妞’和‘贵妃’果实的内源物质含量均在绿果期开始出现显著性变化。

【Objective】Provide reference for the rational application and timely harvesting of mulberries.【Method】Using the fruits of two excellent varieties of Xinjiang,‘Heiniu’and‘Guifei’,with maturity levels of 1-6,the nutritional and functional indicators of the fruits were measured.The content of various indicators in mulberries with different maturity levels was analyzed and compared,and the correlation between maturity and fruit quality was explored.【Result】There was a significant difference in endogenous substance content between the fruits of‘Heiniu’and‘Guifei’at maturity 4,and the overall endogenous substance content of‘Heiniu’fruits was higher than that of‘Guifei’;The content of total phenols,total flavonoids,and anthocyanins was positively correlated with fruit maturity as a whole,and the content of these three substances was highest at maturity of 6,at 54.8,40.1,and 557.9 mg/g,respectively;The protein content of the fruits of‘Heiniu’and‘Guifei’was negatively correlated with fruit maturity.The fruit of‘Heiniu’had the lowest content(0.2 g/kg)at maturity 5,while the fruit of‘Guifei’had the lowest content(0.1 g/kg)at maturity 6.The content of ascorbic acid in Heiniu fruit was negatively correlated with fruit maturity,with a small change in content.The lowest content was at maturity 6(0.7 g/kg),while the ascorbic acid was not detected in the‘Guifei’fruit in the first 3 stages of maturity,and the ascorbic acid appeared from maturity 4,indicating that this stage was the accumulation of ascorbic acid;The content of phenolic acids and total acids were negatively correlated with fruit maturity,reaching the lowest value at maturity of 6.The lowest values of phenolic acid content in‘Black Girl’and‘Guifei’were 30.3 and 2.2 mg/kg,respectively,and the lowest values of total acid content were 10.6 and 7.5 g/kg;Among various amino acids,the average content of aspartic acid in the six mature fruits of‘Heiniu’and‘Guifei’was the highest,at 0.055 and 0.047 mg/g,respectively.Among them,the aspartic acid content was the highest at maturity 1,at 0.078 and 0.104 mg/g,respectively.This indicator could be used as a flavor evaluation indicator for fruits at different maturity stages.【Conclusion】With the increase of maturity,various fruit quality traits show a clear pattern of change.The total nutrient content of the fruits of‘Heiniu’is significantly higher than that of‘Guifei’,and the endogenous substance content of both‘Heiniu’and‘Heiniu’fruits shows significant changes starting from the green fruit stage.